Jiangsu Haifa Machinery Manufacturing Co., Ltd.

Abstract  API 610 13th Edition was released on June 29,2026, approximately five years after the12th Edition released 2021. As a technical team long engaged in the design and manufacture of API 610 high-temperature and high-pressure chemical pumps our focus is not on the edition number itself, but on the quantifiable requirements the new edition imposes on hydraulic selection,-containing structure, hot alignment, mechanical seal interface, and nozzle loads. The 13th Edition does not change the basic classification system for OH, BB, and VS series, but further clarifies the applicable boundaries for new pumps and adjusts NPSH margin, shut-off head, casing strength calculation, high-temperature guiding structure, and high-pressure seal chamber. official materials confirm that the release dates for the 12th and13th Editions are January 26, 1, and June 29, 2026, respectively.Quick Selection Conclusion  For API 610 OH2, BB, BB3, and BB5 chemical pump projects, the key impact of the 13th Edition is not simply increasing material thickness, but more design interfaces into engineering indicators that can be calculated, inspected, and traced. The project technical specification should prioritize reviewing the following: safety margin between NPSHa and NPSH3; H-Q curve variation from rated point to shut-off; pressure stress on casing and fasteners; axial expansion and guiding structure under high-temperature conditions; allowable forces and moments on large-diameter pump nozzles installation dimensions of high-pressure mechanical seal chamber; and whether there is an incorrect independent support at the rear of the OH2 bearing housing.I. Main Differences Between 12th and 13th Editions| Comparison Item | API 610 12th | API 610 13th Edition | | :--- | :--- | :--- | | Release | January 26, 2021 | June 29, 2026 | Scope of Application | Unified requirements for design, manufacture, and acceptance of centrifugal pumps | Clearly specifies primary application to newly manufactured centrifugal pumps; maintenance, upgrade, and refurbishment transitioned to API RP 697 | | NPSH Margin | Determined per 12th Edition data sheet and project requirements | Minimum NPSH margin increased to  m, and datum plane for vertical pumps further clarified | |-Q Curve | Continuously rising curve typically specified by buyer | Default requirement for continuously rising curve from rated point to shut-off, with head rise generally not less than 10% | | Casing Strength | Uses proportional limits of tensile strength and yield strength | ASME BPVC Section II-D allowable stress; rule-based or analysis design permitted | | Fastener Stress | Lacks unified quantitative upper limit | Preload stress not to exceed 80% of minimum yield strength;static test stress not to exceed 90% | | High-Temperature Expansion Control | Determined by pump manufacturer based on structural configuration | Guiding or keyway structure should be emphasized for BB3 above 150°C, and OH2, BB2, BB5 above 260°C | | Nozzle Load Table | Covers up to DN400 Standard load table expanded to DN600 | | Seal Chamber Dimensions One standard seal chamber table, sizes 1–10 | Divided into standard seal chamber and high-pressure seal chamber; sizes expanded to 1–14| High-Pressure Seal Interface | Primarily defined via project data sheet | New standard dimension table applicable for seal chamber pressure not less than 40 |

The above changes are derived from a chapter-by-ch analysis of the official 13th Edition text by experts involved in its revision, covering scope, NPSH, head curve, casing stress, thermal expansion guiding, nozzle loads, and high-pressure seal chamber.

II. OH2 Bearing Housing Rear Support Still Not Permitted  API 610 12th Edition Clause 9.1..1 explicitly states that independent support at the rear bearing housing is not permitted for OH2 pumps. The 13th Edition voting draft retained this requirement, making it a continuation clause, not a new addition. For centerline-supported OH2 pumps, the pump casing, bearing bracket, and rotor system should be allowed to expand in the intended direction during hot operation. Adding a rigid foot at the rear of the bearing housing resting on the baseplate could create an additional constraint point, cold-to-hot coaxiality. The correct approach to ensure structural rigidity is not through rear supports but by: optimizing pump casing centerline feet; verifying the connection area between bearing bracket and casing; strengthening the baseplate crossbeam under the pump; checking API 610 nozzle loads; and completing cold-to-hot alignment and shaft end displacement assessment. User-provided clause screenshots and original materials also clearly indicate the prohibition of rear bearing housing support for OH2 pumps.III. Quantifiable R&D Indicators in 13th Edition Adaptation  In Jiangsu Haifa's technical comparison analysis, we have compiled the following review indicators from the new edition that are most relevant to product R&D:

| R&D Review Item | Suggested Quantifiable Indicator | Main Pump Types Affected |
| :--- | :--- | :--- |
| NPSH Safety Margin | NPSHa – NPSH3 not less than 1 m OH2, BB2, BB3, BB5, VS series |
| Shut-Off Head Rise | Generally not less than 10% relative to rated point OH, BB, and some VS pumps |
| Casing Bolt Preload Stress | Not exceeding 80% of minimum yield strength | High-pressure OH2, BB2,5 |
| Hydrostatic Test Bolt Stress | Not exceeding 90% of minimum yield strength | All pressure-containing pump types |
|-Temperature Guiding Design | BB3 > 150°C; OH2, BB2, BB5 > 260°C | High-temperature hot oil pumps, hydrogenation pumps |
| Standard Nozzle Load Coverage | Expanded to DN600 | Large-flow BB1, BB2, VS pumps |
| High-Pressure Seal Chamber Interface | Focus on checking when seal chamber pressure 40 bar | BB3, BB4, BB5 high-pressure pumps |
| Seal Chamber Size Range | Expanded from 1–10 to 1–14 | Large shaft diameter and high-power pumps |

indicators cannot replace actual project data sheets. Material allowable stress, corrosion allowance, mechanical seal scheme, rotor dynamics, and test levels must still be determined based on medium, temperature, pressure, speed, and buyer's technical specification.IV. Jiangsuifa API 610 Chemical Pump Technical Scope

| Product Series | Structural Form | Flow Range | Head Range | Temperature Range | Design Pressure |
| :--- :--- | :--- | :--- | :--- | :--- |
| HES/OH2 High-Temp & High-Pressure Process Pump | Horizontal, radially split, single-stage overhung, centerline support | 2–2600 m³/h | Up to ~300 m | -80–450°C | 2.5–45 |
| HCSZ High-Pressure Multistage Pump | Single casing, segmental, horizontal multistage | 5–730 m³ | Up to 2800 m | -80–210°C | Up to 30 MPa |
| HDSZ/BB5 High-Pressure Pump | Double casing, barrel-type, horizontal multistage, inner cartridge pull-out | 5– m³/h | Up 3400 m | -80–450°C Up to 35 MPa |

The HCSZ and HDSZ series use back-to-back impeller arrangement, configurable with single-suction or double-s first stage impellers. The HDSZ external pressure casing uses a forged structure, and the inner cartridge can be fully pulled out without moving the inlet/outlet piping. Jiangsu Haifa's official website publishes the capability ranges for the above OH2, HCSZ, and HDSZ series. It should be noted that the series capability range does not mean each pump complies with API 610 13th Edition. The final edition, material class, test scope, mechanical seal, and monitoring configuration should be specified in the inquiry data sheet, technical specification, and contract.

V. Practical Impact on Pump Selection and Project Procurement  After the implementation of the 13th Edition, EPC contractors and end users need to confirm system design pressure NPSH margin, shut-off pressure, and nozzle loads earlier. For BB5 hydrogenation feed pumps, high-pressure water injection pumps, and high circulation pumps, the high-pressure seal chamber dimensions will directly affect the selection of pump shaft shaft sleeve, seal gland, and mechanical seal. Pump manufacturers also need to complete the following during the quotation stage: hydraulic curve and shut-off pressure review; casing finite element or rule-based design assessment; thermal expansion path analysis for-temperature pumps; nozzle load and shaft end displacement verification; chamber pressure and API 682 seal interface check; and deviation explanation for materials, NDT, and test items.

From an engineering implementation perspective, the core value of the13th Edition is reducing interface ambiguity between pump manufacturers, engineering companies, and users, allowing key design conditions to be confirmed before manufacturing.

References  API Standard 610, Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries, 12th Edition, 2021.   Standard 610, Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries, 13th Edition June 2026.   API Recommended Practice 697, Pump Repair.ASME Boiler and Pressure Vessel Code, Section II, Part D.   Simon Bradshaw, API 610 13th Edition—Lucky for Some? Part 1, 2026.Differences Between API 610 12th and 13th Editions for Centrifugal Pumps and Jiangsu Haifa's R&D Adaptation[FAQ]1. After the release of API 610 th Edition, must all 12th Edition pumps be replaced?  No. The 13th Edition further clarifies that its primary scope is newly manufactured centrifugal pumps. Maintenance, refurbishment, and upgrades of existing equipment should be evaluated based on original design conditions, API RP 697, and project owner standards. It is not permissible to simply require complete modification of old pumps to the 13th Edition structure2. Can support feet be added to the rear of the bearing housing for an API 610 OH2 pump?  Not recommended, and it does not comply with the clauses of the 12th Edition. OH2 pumps should withstand loads through centerline support of the pump casing, bearing bracket, and baseplate rigidity not by adding rigid floor-mounted supports at the rear of the bearing housing. support points may also restrict axial thermal expansion of high-temperature pumps.